It has been proposed heretofore that information regarding the operating conditions of a group of ring spinning machines in a textile mill be gathered for use in tending such machines and more efficiently managing the manufacture of yarns by such machines. For example, it has been disclosed in such prior patents as Ford et al U.S. Pat. No. 3,523,413; Bryan Jr. et al U.S. Pat. No. Re. 27,501; and Saunders U.S. Pat. No. 3,680,298, owned in common with the present invention, that at least one traveling unit be supported for travel along a predetermined path of travel for traversing one or more ring spinning machines and that information be gathered from detectors traveling with such a traveling unit. To the extent that the disclosures of the aforementioned patents are necessary or appropriate to an understanding of present invention, those prior patents are hereby incorporated by reference into the present description. As will be apparent to persons skilled in the applicable arts from a study of the aforementioned patents, a data system may be provided in connection with a group of ring spinning machines which is responsive to detectors on a traveling unit for determining the condition of each machine of a traversed group of machines.
Information gathering and processing apparatus and methods of the types described in the aforementioned patents have achieved some acceptance in textile mill operations and, as so accepted, have included frequency modulation transmitters and receivers of the type generally described in aforementioned Saunders U.S. Pat. No. 3,680,298 in column 7 at line 45. The data link means provided by a correlated transmitter and receiver of the type described in the aforementioned Saunders U.S. Pat. No. 3,680,298 additionally will be recognized as having utility outside the specific field of use to which the present description is directed.
As the development of such textile machine information gathering apparatus and methods has proceeded, it has been realized that efficient and accurate communication of data would be improved by enhancing performance of the data link means provided by a transmitter and receiver. In particular, such enhanced performance has been contemplated as being achievable by means of more accurate control over frequency bands employed for communication. Such accurate control, when accomplished, has additionally been contemplated as opening the possibility of reduced band width requirements, whereby greater "packing" of channels within particular broad band widths of frequencies would become attainable.